Lighting in MaxImmerse (EN)

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This section does not readily fit into a category but needs to be addressed. There are multiple ways to do the similar lighting effects in NetImmerse. The most appropriate lighting technique depends on the type of effect, the textures used, geometry of the scene, and the target platform. Here are a couple of factors to consider when tackling a lighting problem: Is the lighting effect moving or stationary? If it is stationary, will the light always be on, or will I sometimes want to turn it off? (See charts below for some answers).

Lighting Techniques

Type of Lighting	Lighting included in Base Texture	Dark Map	Vertex Colors	Dynamic Light	Projected Texture Effect
Stationary Always On	POSSIBLE	POSSIBLE	POSSIBLE	POSSIBLE BUT OVERKILL	POSSIBLE BUT OVERKILL
Stationary Sometimes On	NOT POSSIBLE W/O ADDITIONAL PROGRAMMING	POSSIBLE	POSSIBLE	POSSIBLE BUT OVERKILL	POSSIBLE BUT OVERKILL
Dynamic (moving)	NOT POSSIBLE W/O ADDITIONAL PROGRAMMING	NOT POSSIBLE W/O ADDITIONAL PROGRAMMING	NOT POSSIBLE W/O ADDITIONAL PROGRAMMING	POSSIBLE	POSSIBLE

Considerations for lighting in MaxImmerse

Lighting Included in Base Texture	Dark Map	Vertex Colors	Dynamic Lights	Projected Texture Effects
May need very large texture	Can be expensive on some graphics cards	Dependent on tessellation	Dependent on tessellation	Overkill if light is not moving since processed every frame
	May not be supported on some graphics cards		Overkill if light is not moving since processed every frame

Advantages for lighting in MaxImmerse

Lighting Included in Base Texture	Dark Map	Vertex Colors	Dynamic Lights	Projected Texture Effects
Can make very specific textures	Can be used in several places, thus lowered VRAM requirements	Fast	Great for moving lights	Great for moving lights
Very fast if lots of VRAM is available	Not tessellation dependent			Not tessellation dependent

Dynamic Lighting in MaxImmerse

Often, the easiest way to set up lighting is with standard lights in Max. However, dynamic lights are expensive, and their use is totally overkill if the light is not moving. If you need a light to move around the scene, then you should consider dynamic lights. Remember, the way the lights work is to compute the lighting on the vertices for every frame, so your face count or tessellation will usually have to be high to achieve a pleasing effect. However, it should be used judiciously and with as few lights as possible so your application can run at the highest speed.

Another type of dynamic lighting is a Projected Texture Effect. This option is outlined in the section on Dynamic Multi-Texturing. Projected textures are not dependent on the tessellation of an object, but the lighting is still computed every frame, so it is still very expensive.

Static Lighting in MaxImmerse

When trying for an interesting static lighting effect, one of the easiest and best ways to do this is to embed

the lighting within the texture. You can have this in combination with other effects listed below. You can also rely on the texture standing by itself with no additional lighting. If that is the case, set your “Apply Mode” to REPLACE, so no other lighting will affect your texture. Replace Mode works well with billboard or other plane geometry, since dynamic lighting can destroy the illusion of 3D with these objects. However, including the lighting in the base texture can result in large textures. You’ll want to keep this in mind, since texture memory is usually limited. The following are some other alternatives.

Use vertex colors. By setting vertex colors, you can light each individual object uniquely without having to consider the expense of a lot of dynamic lights. The drawback of this feature is that your mesh may need more tessellation to prevent artifacts of the vertex lighting from showing through. However, the tessellation drawback also applies to dynamic vertex lighting.

Use dark maps. In this case, you can use a small texture with tiling on the whole surface of an object and use a separate texture (your dark map) once across the same surface. In general, the need to have a highly detailed dark map is not very common and usually this is a great solution. However, it is a relatively expensive operation on some graphics cards and should not be used heavily if the target platform will use such cards. A few cards and platforms do not support dark maps at all, so check your requirements.

When lights are not moving in a scene, DO NOT use dynamic lighting. You should use vertex colors or dark maps. If you find it easier to use dynamic lights to light your scene, your programmer may be able to process your scene by automatically burning in dynamic lights into the vertex colors for you. Check with your programmer if you need this option.

Last but not least is the option of additive mode transparency. Textures can be added on top of one another in an object to give a certain lighting effect. This particular type of lighting takes a little practice to achieve the right effect, but can yield some nice results, such as halos around lights. It is also not too expensive an operation.